Halogenated 1,3-dioxolanes and derivatives

ABSTRACT

There are disclosed halogenated dioxolanes of a specified formula, dioxoles made therefrom, polymers of the dioxoles, and processes for making the dioxolanes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to halogenated dioxolanes and dioxoles, theirpreparation and polymers of the dioxoles.

2. References

U.S. Pat. No. 2,925,424, issued to Simmons on Feb. 16, 1960, disclosescyclic fluoroketals of the formula ##STR1## prepared by reactingfluoroketones with β-haloethanol; wherein R_(x) and R_(y) areperhalohydrocarbyl radicals of 1 to 7 carbon atoms, and R_(z) is adivalent hydrocarbyl or halohydrocarbyl radical of 1 to 12 carbon atoms.

U.S. Pat. No. 3,308,107, issued to Selman, et al., on Mar. 7, 1967,discloses perfluoro-2-methylene-4-methyl-1,3-dioxolane, its preparationfrom perfluoro-2,4-dimethyl-2-fluoroformyl-1,3-dioxolane, and polymersthereof.

U.S. Pat. No. 3,316,216, issued to Fawcett, et al., on Apr. 25, 1967,discloses the preparation of fluorinated dioxolanes of the formula##STR2## where R, R' and R" can include H, hydrocarbyl, haloalkyl andvarious other carbon-containing groups, and X and X¹ can include H,halogen and perfluoroalkyl, from fluoroketones and epoxides.

U.S. Pat. No. 3,324,144, issued to Coe, et al., on June 6, 1967,discloses fluorodioxolanes ##STR3## prepared from ketones and epoxides.

U.S. Pat. No. 3,379,736, issued to Dietrich, et al., on Apr. 23, 1968,discloses 4-methylene-1,3-dioxolanes containing either hydrogen and achlorinated methyl group or a methylene or a chlorinated methylene groupin the 2-position.

U.S. Pat. No. 3,450,716, issued to Selman on June 17, 1969, disclosesperfluoro-4-oxo-2,5-dimethyl-2-fluorocarbonyl-1,3-dioxolane.

U.S. Pat. No. 3,532,725, issued to Dorfman, et al., on Oct. 6, 1970,discloses the photochlorination of alkyl and aralkyl ester groups offluorinated esters in the presence of Cl₂, UV radiation and, optionally,CCl₄ as solvent.

U.S. Pat. No. 3,555,100, issued to Garth, et al., on Jan. 12, 1971,discloses the decarbonylation of fluorocarboxylic acid fluorides in thepresence of SbF₅.

U.S. Pat. No. 3,557,165, issued to Dorfman, et al., on Jan. 19, 1971,discloses the conversion to acyl halides, in the presence of Lewisacids, of fluorinated esters wherein the ester groups containpolyhalogenated alkyl or aralkyl groups. The disclosed Lewis acidsinclude FeCl₃, SbCl₅, ZnCl₂, ZnCl₄, BF₃, BCl₃, MoCl₅, tin chlorides andmetal chlorides, bromides and iodides such as ZrI₄ and antimony bromide.

U.S. Pat. No. 3,749,791, issued to Terrell, et al., on July 31, 1973,discloses halogen-substituted 2,2-bis(trifluoromethyl)-1,3-dioxolanes##STR4## where X is Cl or F and X' is H, Cl, or F, and their preparationby hydrogenation of 2,2-bis(trifluoromethyl)-1,3-dioxolane.

U.S. Pat. Nos. 3,865,845 and 3,978,030, issued to Resnick on Feb. 11,1975 and Aug. 31, 1976, respectively, disclose fluorinated dioxoles ofthe formula ##STR5## where R¹ and R² are both perhalogenated hydrocarbylradicals of 1 to 3 carbon atoms containing at least one F atom andpreparation of said dioxoles by reacting the corresponding dioxolaneswith Mg. The dioxolanes are prepared by fluorination with SbF₃ -SbCl₄ at120° C. of 2,2-bis-(perhaloalkyl)-4,4,5,5-tetrachloro-1,3-dioxolanes,which in turn are prepared from haloketones in accordance with themethod described in U.S. Pat. No. 2,925,424.

U.S. Pat. No. 4,182,718, issued to Crutchfield, et al., on Jan. 8, 1980,discloses 1,3-dioxolane and 1,3-dioxane polycarbonates and theirprecursors having the formula: ##STR6## wherein X may be selected fromthe group consisting of H, CCl₃, CO₂ R, where R is H or lower alkyl, CO₂M, where M is alkali metal, NH₄ or trialkanolammonium, at least three ofthe X substituents are other than hydrogen, and n is 1 or 2. Thecompounds are prepared by the reaction of a halogenated alcohol with areactive carbonyl to form a halogenated hemi-ketal, followed by reactionwith a base to effect cyclization.

U.S. Pat. No. 4,287,124, issued to Siegemund, et al., on Sept. 1, 1981,discloses the preparation of dioxolanes of the formula ##STR7## whereinX and Y, independently, are F or CF₃ and R¹ and R² are H or CH₃, byreacting certain acyl halides with a metal fluoride or ammoniumfluoride.

U.S. Pat. No. 4,393,227, issued to Squire on July 12, 1983, discloses aprocess for dechlorinating organic compounds having vicinal chlorineatoms, in particular the preparation of dioxoles from dioxolanes asfollows: ##STR8## +MgCl₂, where each of Y and Z independently is H, Clor F, and each of R³ and R⁴ independently is H, F or trifluoromethyl.

U.S. Pat. No. 4,399,264, issued to Squire on Aug. 16, 1983, disclosesperfluoro-1,3-dioxole, homopolymers and copolymers thereof, and aprocess for making the dioxole.

U.S. Pat. No. 4,431,786, issued to Squire on Feb. 14, 1984, disclosesfluorodioxoles of the formula ##STR9## in which Y is hydrogen orchlorine; Z is hydrogen, fluorine, or chlorine; and R is fluorine or thetrifluoromethyl group; with the proviso that when R is trifluoromethyl,only one of Y and Z can be hydrogen or chlorine. The patent alsodiscloses polymer and copolymers of these dioxoles.

U.S. Pat. Nos. 4,429,143 and 4,496,750, issued to Anderson, et al., onJan. 31, 1984 and Jan. 29, 1985, respectively, disclose halogenateddioxolanes of the formula: ##STR10## wherein X₁ is Cl, F, COF, COCl, CO₂CCl₃, CO₂ R or CO₂ M; R is H or alkyl of 1 to 4 carbon atoms; M is analkali metal ion or ammonium ion; R_(F) is a perfluoroalkyl group of 1to 4 carbon atoms; X₂, X₃, X₄ and X₅, independently are H, Cl or F; withthe proviso that when X₂, X₃, X₄ and X₅ are each H, X₁ is CO₂ R or CO₂M. The patents also discloses perhalogenated dioxoles of the formula:##STR11## wherein Y₁, Y₂ and Y₃, independently are F or Cl. The patentsalso disclose homopolymers, copolymers of the dioxoles and methods ofmaking the compounds.

Simmons, et al., Journal of the American Chemical Society 82, 2288(1960), disclose the preparation of dioxolanes and substituteddioxolanes and specifically mentions that 1,3-dioxolanes were obtainedfrom hexafluoroacetone, sym-difluorotetrachloroacetone andtrifluoroacetaldehyde. The general method disclosed for preparing thedioxolanes is the reaction of the appropriate carbonyl compound with anappropriately substituted ethylene halohydrin.

SUMMARY OF THE INVENTION

The present invention provides dioxolanes of the formula ##STR12##wherein: X¹, X², X³ and X⁴ are each --H; each --Cl; or independently--Cl or --F with at least one being --F, and at least one of X¹ and X²and at least one of X³ and X⁴ being --Cl;

R² _(F) is --R_(F), --H, --Cl, --F or --C(O)Y';

R_(F) is a perfluorinated linear or branched alkyl group having 1 to 14carbon atoms and terminally substituted with --F, --Cl, Br, --OR, --OC₆F₅, --SR', --SO₂ R', --SO₂ F, --N₃, --CN, --COOR', --OCCl₃, --SCl, --SO₂Cl, --C(O)OCCl₃, --C(O)Cl or --C(O)F, or said perfluorinated alkyl groupalso containing ether oxygen;

R' is an alkyl group of 1 to 4 carbon atoms;

Y' is --OCH₂ CH₂ X wherein X is Cl or Br;

R is an alkyl group of 1 to 4 carbon atoms, --CH₂ CF₃ or --C₆ H₅ ;

Y⁴ is --R'_(F) Q, --R² _(F), --R'_(F) C(O)CF₃, --OCCl₃ or OR with R'_(F)being a single bond or a perfluoroalkylene group of 1 to 4 carbon atoms,or said perfluoroalkylene group containing ether oxygen;

Q is ##STR13## with the proviso that: (ii) when X¹, X², X³ and X⁴ areeach H:

(a) R² _(F) is other than --Cl or --F, Y⁴ is other than --OCCl₃ or --R²_(F) where --R² _(F) is --C(O)Y', and R_(F) is a perfluorinated alkylgroup terminally substituted with --F, --Cl, --OR, --OC₆ F₅, --SR',--SO₂ R', --SO₂ F, --N₃, --CN or --COOR', or said perfluorinated alkylgroup also containing ether oxygen;

(b) when R² _(F) is --H or --C(O)Y', Y⁴ is R_(F) where R_(F) isperfluoroethyl terminally substituted with --F, --N₃, --OC₆ F₅ or --SR';and

(c) when R² _(F) is R_(F) having terminal substitution with --F or --Cl,then Y⁴ is other than --H, --OR or --R_(F) having terminal substitutionwith --F or --Cl;

(ii) when X¹, X², X³ and X⁴ are each --Cl:

(a) R² _(F) is other than --H, --C(O)Y' or --F, Y⁴ is other than --OR,and R_(F) has terminal substitution by other than --OR, --SR', --SO₂ R',--N₃, --COOR', or --C(O)F;

(b) when R² _(F) is R_(F) having terminal substitution with --F or --Cl,Y⁴ is other than --Cl or --R² _(F) having terminal substitution with --For --Cl; and

(c) when R² _(F) is --Cl, Y⁴ is --R'_(F) Q;

(iii) when X¹, X², X³ and X⁴ are each --Cl or --F with at least onebeing --F, and at least one of X¹ and X² and at least one of X³ and X⁴being --Cl:

(a) R² _(F) is other than --H, --C(O)Y' or --Cl, Y⁴ is other than--OCCl₃ or --OR, and R_(F) has terminal substitution with --F, --Cl,--OC₆ F₅, --SO₂ F, --CN, --SO₂ Cl, --C(O)Cl or --C(O)F;

(b) when R² _(F) is R_(F) having terminal substitution with --F or --Cl,Y⁴ is other than --F or --R² _(F) having terminal substitution with --For --Cl; and

(c) when R² _(F) is --F, Y⁴ is --R'_(F) Q.

The invention also provides a dioxole of the formula ##STR14## whereinX⁵ and X⁶ are independently --F or --Cl with at least one being --F;

R³ _(F) is --F, a perfluorinated linear or branched alkyl group having 1to 14 carbon atoms and terminally substituted with --F, --Cl, --OC₆ F₅,--SO₂ Cl, --SO₂ F, --CN, --C(O)F or --C(O)OR", or said perfluorinatedalkyl group also containing ether oxygen;

R" is --CH₃, --C₂ H₅ or --CH₂ CF₃ ;

Y⁵ is --F, --R'_(F) Q', --R³ _(F) or --R'_(F) C(O)CF₃ ;

Q' is ##STR15## R'_(F) is a single bond or a perfluorinated alkyl grouphaving 1 to 4 carbon atoms or said group containing ether oxygen;

with the proviso that:

(a) when R³ _(F) is a perfluorinated alkyl group terminally substitutedwith --F or --Cl, Y⁵ is other than --F or --R³ _(F) having terminalsubstitution with --F or --Cl; and

(b) when R³ _(F) is --F, Y⁵ is --R'_(F) Q'.

Also provided are processes for preparing the dioxolanes andhomopolymers and copolymers made from the dioxoles.

DETAILED DESCRIPTION OF THE INVENTION

The dioxolanes and dioxoles of the invention have the formulas set forthearlier herein. For the dioxolanes of the invention, preferredembodiments are as follows:

(a) when X¹, X², X³ and X⁴ are each hydrogen:

R² _(F) is --R_(F), preferably having 1 or 2 carbon atoms and terminalsubstituents other than --F or --Cl, the substituents most preferablybeing --CN, --SR', --SO₂ F, --OC₆ F₅ or --C(O)OCH₃ ; and

Y⁴ is --H, --OCH₃, --CF₃ or --C₂ F₅ ;

(b) when X¹, X², X³ and X⁴ are each --Cl:

R² _(F) is perfluorinated alkyl, preferably having 1 or 2 carbon atomsand terminal substituents other than --F or --Cl, the substituents mostpreferably being --CN, --C(O)Cl, --C(O)OCCl₃, --SO₂ Cl, --SO₂ F or --OC₆F₅ ;

Y⁴ is --Cl, --OCCl₃, --CF₃ or --C₂ F₅ ; and

(c) when X¹, X², X³ and X⁴ are each --Cl or --F with at least one being--F, and at least one of X¹ and X² and at least one of X³ and X⁴ beingCl:

R² _(F) is perfluorinated alkyl, preferably having 1 or 2 carbon atomsand terminal substituents other than --F or --Cl, the substituents mostpreferably being --C(O)Cl, --C(O)F, --CN, --SO₂ F or --OC₆ F₅ ; and

Y⁴ is --F, --CF₃ or --C₂ F₅.

Preferred dioxoles of the invention are those where X⁵ and X⁶ are each--F; R³ _(F) is perfluorinated alkyl, preferably having 1 or 2 carbonatoms and terminal substituents other than --F or --Cl, the substituentsmost preferably being --CN, --C(O)F, --C(O)OCH₃, --SO₂ F or --OC₆ F₅ ;and Y⁵ is --F, --CF₃ or --C₂ F₅.

Dioxolanes of formula I wherein X¹, X², X³ and X⁴ are --H, R² _(F) is--R_(F), --R_(F) is perfluorinated alkyl, and Y⁴ is --H, --OR or --CF₂CF₂ Z where Z is --F, --N₃, --OC₆ H₅, --SR' or --OC₆ F₅, and R' is analkyl group of 1-4 carbon atoms, are prepared by reacting a 2-chloro- or2-bromoethyl ester of the appropriate fluoroalkylcarboxylic acid, saidester having the formula R_(F) CO₂ CH₂ CH₂ X wherein X and R_(F) are aspreviously defined herein, with a compound of the formula MY¹ in asuitable solvent. Y¹ is equal to --H, --OR or --CF₂ CF₂ Z where R and Zare as previously defined herein; and M is Na, Li, K or NR'₄ with R'being an alkyl group of 1-4 carbon atoms. The process can be describedby the following equations:

    R.sub.F C(O)Y'+MY.sup.1 →QY.sup.1                   ( 1)

where Y¹ is other than --OR with R being an alkyl group of 1-4 carbonatoms and the other symbols are as previously defined, and

    R.sub.F C(O)Y'+MY.sup.1 →QY.sup.1 +QY'              (1a)

where Y¹ is --OR with R being an alkyl group of 1-4 carbon atoms and theother symbols are as previously defined. The relative amounts of the twoproducts in equation (1a) are determined by the relative amounts of thetwo starting materials and the basicity of the --OR group with the QY¹product always being the major product. The process is conducted at atemperature of from about -20° to 80° C., preferably from about 0° toabout 50° C. Reaction time may vary from a few minutes to several weeks,depending upon reactant and solvent. A pressure of about 101 kPa (14.7psi) is preferred, but pressure can be from about 6.9 to about 6900 kPa,particularly when tetrafluoroethylene is a reactant, i.e.,tetrafluoroethylene is used to prepare MCF₂ CF₂ Z which serves as MY¹ isthe reaction above. Solvents suitable for this process are dipolaraprotic materials such as dimethyl sulfoxide, diglyme, tetrahydrofuran,dimethylformamide, and the like but dimethyl sulfoxide is preferred. Thereactants are generally present in equivalent amounts, but the ratio ofequivalents can be varied to promote efficient utilization of the moreexpensive reactant. The resulting product can be isolated by filtrationfollowed by distillation or crystallization; or by dilution of theresulting reaction mixture with water and subsequent purification of thewater insoluble product.

Dioxolanes of the foregoing class wherein Y¹ is --OR and R is an alkylgroup of 1-4 carbon atoms, can also be prepared by reacting theperfluoroalkylacid ester, R_(F) CO₂ R with a compound of the formulaMOCH₂ CH₂ X where M and X are as previously defined. This process isdescribed by the following equation:

    R.sub.F CO.sub.2 R+MY.sup.1 →QOR+QY.sup.1           ( 2).

The process conditions and suitable solvents are the same as thoseprescribed for reactions (1) and (1a). This process is preferred formaking QOR dioxolanes because the relative amount of the primary productis greater for this process than for the process of equation 1(a).

The invention also provides a process for preparing dioxolanes of theformula ##STR16## wherein: R'_(f) is --H, --C(O)Y' or Q';

Y' is --OCH₂ CH₂ X where X is --Cl or --Br;

Q' is ##STR17## Z is --F, --N₃, --OC₆ H₅, --SR' or OC₆ F₅ ; and R' is analkyl group of 1 to 4 carbon atoms.

The process comprises reacting (a) 2-chloro- or 2-bromoethylformate or(b) bis(2-chloroethyl) oxalate or bis(2-bromoethyl) oxalate with acompound of the formula MCF₂ CF₂ Z in a suitable solvent. The processcan be described by the following equations:

    HC(O)Y'+MY"→Q'H                                     (3)

    [Y'C(O)].sub.2 +MY"→Y'C(O)Q'+(Q').sub.2             ( 3a)

wherein Y" is CF₂ CF₂ Z. The process can be conducted in a suitablesolvent at a temperature of from about -20° to 80° C., preferably fromabout 0° to about 50° C. Pressure can vary over the same range as forreaction (1). The pressure can be from about 6.9 kPa whentetrafluoroethylene is used as a reactant to prepare MCF₂ CF₂ Z.Elevated pressures, from about 6.9 kPa to about 6900 kPa are preferred.Suitable solvents and other reaction conditions are similar to those forreactions (1) and 1(a). Ether solvents are preferred. Process (3)provides preparation of dioxolanes of the invention wherein X¹, X², X³and X⁴ are each hydrogen; R² _(F) is --H, --C(O)Y' or --CF₂ CF₂ Z; andY⁴ is (a) R'_(F) Q where R'_(F) is a single bond or (b) R² _(F) whereR².sub. F is --R_(F) and R_(F) is --CF₂ CF₂ Z, provided that either R² For Y⁴ is --CF₂ CF₂ Z.

Dioxolanes of the invention wherein X¹, X², X³, and X⁴ are each --H, Y⁴is --OR, R_(F), R'_(F) C(O)R_(F), or R'_(F) Q and Q is ##STR18## areprepared by reacting in a suitable solvent a compound of the formulaR_(F) C(O)Y² with a compound of the formula MY³ to produce a compoundhaving the formula R_(F) C(OM)Y² Y³ which is then reacted with2-chloroethanol or 2-bromoethanol to produce the desired dioxolane. Inthe foregoing formulas for this process (4), Y² and Y³ are theindependently --OR, R_(F), R'_(F) C(O)CF₃, or R'_(F) Q, provided that atleast one of Y² and Y³ is --OR. The other symbols are as previouslydefined. The process can be described by the following equation (4):##STR19## In equation (4) Y⁶ is equal to Y² or Y³ depending upon whichof Y² or Y³ is --OR. The process is conducted at a temperature of fromabout -20° C. to about 80° C., preferably from about 0° C. to about 50°C. Suitable solvents include pentane, ether and dimethylsulfoxide. Otherprocess conditions are the same as those prescribed for reactions (1)and (1a).

The dioxolanes of formula I wherein X¹, X², X³ and X⁴ are each Cl or areindependently Cl or F with at least one being F and at least one of X¹and X² and at least one of X³ and X⁴ being Cl can be prepared from thecorresponding dioxolanes of formula I wherein X¹ to X⁴ are each --H byknown processes, particularly those described in U.S. Pat. Nos.4,429,143 and 4,496,750 issued to Anderson et al., 4,393,227 and4,399,264 issued to Squire, and 3,865,845 and 3,978,030 issued toResnick.

The dioxoles of the invention can be prepared by known processesdescribed in the aforementioned patents.

The dioxoles of the invention can be homopolymerized, or copolymerizedwith one or more polyhalogenated vinyl monomers of the formula

    CZ.sup.1 Z.sup.2 ═CF.sub.2

wherein Z¹ is H, F or Cl; Z² is H, F, Cl or OR_(H) ; R_(H) isperhaloalkyl of 1 to 4 carbon atoms, --CF₂ --_(n) CF═CF₂, or --CF₂CF(CF₃)O--_(n) CF₂ CF₂ Z³ ; n is an integer from 0 to 6; Z³ is SO₂ F,CO₂ R⁶ or CN; and R⁶ is H or an alkyl group of 1 to 4 carbon atoms. Theycan also be copolymerized with perfluoro-2,2-bis(methyl)-1,3-dioxole.Tetrafluoroethylene, chlorotrifluoroethylene, perfluoromethylvinyl etherand perfluoropropylvinyl ether are preferred comonomers. Polymers of theinvention will generally contain about 0.5 to 100 mol percent of unitsderived from monomers of the invention.

The polymers are prepared by well-known free-radical techniques,particularly those employed for copolymerization of tetrafluoroethylenewhich are described in the literature. Preferably, polymerization isconducted in nonaqueous media in a perfluorinated or fluorine-containingperhalogenated solvent, such as perfluorodimethylcyclobutane or1,1,2-trichlorotrifluoroethane and the like. Useful free-radicalinitiators include a perfluorocarbon peroxide such as perfluoropropionylperoxide or an azo compound such as azo-bis(isobutyronitrile).Polymerization can be conducted at a temperature of from about 0° C. toabout 200° C., preferably from about 20° C. to about 80° C., and at apressure of from less than about 101 kPa to about 0.02 MPa. The polymersof the invention are expected to have increased Tg's. The dioxoles ofthe invention in conferring higher Tg's lead to higher services (use)temperatures in the copolymers made therefrom. The dioxoles of theinvention contain functional groups which allow crosslinking and otherchemical modifications of polymers made therefrom. This enables thepolymer to be converted to conductive membranes or ion exchangematerials of high stability.

The invention is further illustrated by the following examples in whichpercentages and ratios are by weight and temperatures are in degreesCelsius unless otherwise stated. The dioxolanes illustrated in theexamples are listed in Tables 1-3. The compounds are coded in theexamples pursuant to the numbers specified in Tables. For all thedioxolanes in Examples 1-17, X¹, X², X³ and X⁴ are H (Table 1). For thedioxolanes in Examples 18, 19, 21, 22 and 24, X¹ to X⁴ are each --Cl.For the dioxolanes in Table 3 X¹ -X⁴ are --F or --Cl with at least onebeing --F. For all these dioxolanes X² and X³ were considered to be --Cland X⁴ to be --F. The examples having an asterisk beside them indicateexamples which illustrate a process of the invention only with theproducts being outside of the present invention.

                  TABLE 1    ______________________________________                                           Com-           Pro-                            pound    Example           cess   R.sub.F.sup.2 Y.sup.4    Code    ______________________________________    1(a)*  1(a)   CF.sub.3      OCH.sub.3   1    1(a)*  1(a)   CF.sub.3      OCH.sub.2 CH.sub.2 Cl                                            2    1(b)*  2      CF.sub.3      OCH.sub.3   1    1(b)*  2      CF.sub.3      OCH.sub.2 CH.sub.2 Cl                                            2    2*     1(a)   F(CF.sub.2).sub.7                                OCH.sub.3   3    2*     1(a)   F(CF.sub.2).sub.7                                OCH.sub.2 CH.sub.2 Cl                                            4    3*     1      CF.sub.3      H           5    4*     1      CF.sub.3      OC.sub.6 H.sub.5                                            6    5      1      CF.sub.3      C.sub.6 H.sub.5 OCF.sub.2 CF.sub.2                                            7    6      3      H             C.sub.6 H.sub.5 OCF.sub.2 CF.sub.2                                            8    7      3(a)   Q'            C.sub.6 H.sub.5 OCF.sub.2 CF.sub.2                                            9    7      3(a)   CO.sub.2 CH.sub.2 CH.sub.2 Cl                                C.sub.6 H.sub.5 OCF.sub.2 CF.sub.2                                           10    8(a)   1      CF.sub.3      N.sub.3 CF.sub.2 CF.sub.2                                           11    8(b)   4      CF.sub.3      N.sub.3 CF.sub.2 CF.sub.2                                           11    8(b)   4      CF.sub.3      CNCF.sub.2 12    9(a)   2      CH.sub. 3 OCF.sub.2 CF.sub.2                                OCH.sub.3  13    9(a)   2      CH.sub.3 OCF.sub.2 CF.sub.2                                OCH.sub.2 CH.sub.2 Cl                                           14    9(b)   4      CH.sub.3 OCF.sub.2 CF.sub.2                                OCH.sub.3  13    10     2      CH.sub.3 O.sub.2 CCF.sub.2 CF.sub.2                                OCH.sub.3  15    10     2      CH.sub.3 O.sub.2 CCF.sub.2 CF.sub.2                                OCH.sub.2 CH.sub.2 Cl                                           16    11     2      CNCF.sub.2    OCH.sub.3  17    11     2      CNCF.sub.2    OCH.sub.2 CH.sub.2 Cl                                           18    12     4      CH.sub.3 O.sub.2 CCF.sub.2                                CH.sub.3 O.sub.2 CCF.sub.2                                           19    13     4      CNCF.sub.2    CF.sub.3   20    13     4      N.sub.3 CF.sub.2 CF.sub.2                                CF.sub.3    20a    14     4      CF.sub.3      Q          21    14     4      CF.sub.3      C(O)CF.sub.3                                           22    15            CH.sub.3 OCF.sub.2 CF.sub.2                                CH.sub.3 OCF.sub.2 CF.sub.2                                           23    16            CF.sub.3      CF.sub.2 OCF(CF.sub.3)--                                           24                                CO.sub.2 CH.sub.3    17*    1      CF.sub.3      CF.sub.2 CF.sub.3                                           25    ______________________________________

                  TABLE 2    ______________________________________           Source of                       Com-           Starting                        pound    Example           Dioxolane R.sub.F.sup.2                                 Y.sup.4   Code    ______________________________________    18     Ex. 1(b)  CF.sub.3    OCCl.sub.3                                           26    18     Ex. 1(b)  Cl          CF.sub.3  27    19     Ex. 10    Cl.sub.3 CO(O)C--                                 Cl        28                     CF.sub.2 CF.sub.2    21               Cl.sub.3 COCF.sub.2 CF.sub.2                                 CF.sub.2 CF.sub.2 OCCl.sub.3                                           31    22     Ex. 9     Cl.sub.3 COCF.sub.2 CF.sub.2                                 Cl        32    24     Ex. 8(b)  CF.sub.2 CN CF.sub.3  33    ______________________________________

                  TABLE 3    ______________________________________           Source of           Starting                      Compound    Example           Dioxolane R.sub.2 F      Y.sup.4                                         Code    ______________________________________    20     Ex. 19    F(O)CCF.sub.2 CF.sub.2                                    F     29a    20     Ex. 19    Cl(O)CCF.sub.2 CF.sub.2                                    F     30a    20     Ex. 19    Cl(O)CCF.sub.2 CF.sub.2                                    F     29b    20     Ex. 19    CH.sub.3 O(O)CCF.sub.2 CF.sub.2                                    F    29    20     Ex. 19    CH.sub.3 O(O)CCF.sub.2 CF.sub.2                                    F    30    25     Ex. 24    CF.sub.2 CN    CF.sub.3                                         34    25     Ex. 24    CF.sub.2 CN    CF.sub.3                                         35    ______________________________________

EXAMPLE 1 2-Methoxy-2-trifluoromethyl-1,3-dioxolane (1) and2-(2-chloroethoxy)-2-trifluoromethyl-1,3-dioxolane (2)

This Example illustrates a process of the invention only.

A. 2-Chloroethyl trifluoroacetate, b.p. 66°-68° at 20 kPa (150 mm) wasprepared in 81% yield by the addition of one equivalent of pyridine to amixture of one equivalent each of trifluoroacetyl chloride and2-chloroethanol in ether solution. The product was isolated byfiltration and distillation of the filtrate.

Anal. Calcd. for C₄ H₄ ClF₃ O₂ : C, 27.21; H, 2.28. Found: C, 27.74; H,2.54.

2-Chloroethyl trifluoroacetate can be more conveniently prepared byreaction of equimolar amounts of trifluoroacetic acid and2-chloroethanol at 25° in the presence of concentrated sulfuric acid forone day followed by distillation.

    CF.sub.3 CO.sub.2 CH.sub.2 CH.sub.2 Cl+CH.sub.3 ONa→1+2

A suspension of 5.4 g (0.10 mol) of sodium methoxide in 50 mL oftetrahydrofuran (THF) was stirred at -20° to -10° while 17.7 g (0.10mol) of 2-chloroethyl trifluoroacetate were added dropwise. Theresulting clear solution was allowed to warm with precipitationcommencing at about 10° and a slow exotherm ensuing to 35°. The mixturewas maintain below 35° until the exotherm subsided and then was stirredfor 4 h. Filtration and fractionation of the filtrate gave 7.4 g (43%yield) of 2-methoxy-2-trifluoromethyl-1,3-dioxolane, b.p. 61°-62° at 3.3kPa (25 mm). IR (neat): 3000, 2965, 2925, and 2680 (sat'd CH), 1250-1100cm⁻¹ (CF, C--O). NMR (CCl₄): ¹ H 4.17 (m, 4H, ring CH₂ and 3.33 ppm (s,3H, OCH₃); ¹⁹ F-85.0 ppm (s, CF₃).

Anal.: Calcd. for C₅ H₇ F₃ O₃ : C, 34.89; H, 4.10. Found: C, 34.88; H,3.94.

Further fractionation of the filtrate gave 1.6 g (14% yield based on theester) of 2-(2-chloroethoxy)-2-trifluoromethyl-1,3-dioxolane, b.p.103°-104° at 3.3 kPa (25 mm). IR (neat): 2985 and 2930 (sat'd CH),1250-1000 cm⁻¹ (CF, C--O). NMR (CCl₄): ¹ H 4.20 (m, 4H, ring CH₂), 3.81(m, 2H, CH₂), and 3.62 ppm (m, 2H, CH₂); ¹⁹ F-84.9 (s, CF₃).

Anal. Calcd for C₆ H₈ ClF₃ O: C, 32.67; H, 3.65; Cl, 16.08. Found: C,32.79; H, 3.45; Cl, 15.92.

B. CF₃ CO₂ CH₃ +ClCH₂ CH₂ OH+NaH→1+2

A mixture of 42.0 g (0.33 mol) of methyl trifluoroacetate, 26.6 g (0.33mol) of 2-chloroethanol, and 150 mL of dimethylsulfoxide (DMSO) wasstirred at 10°-20° while 15.8 g (0.33 mol) of 50% NaH in mineral oil wasadded portionwise. The resulting mixture was stirred at 20° for 2 h, at25° for several days, and then poured into 1 L of water. The resultingaqueous layer was extracted with 100 mL of ether. The organic layerswere combined, then washed twice with water, dried over CaSO₄, anddistilled to give 35.6 g (63% yield ) of2-methoxy-2-trifluoromethyl-1,3-dioxolane, b.p. 60°-65° at 3.3 kPa (25mm), and a residue containing about 4.8 g (7% yield) of by-product2-(2-chloroethoxy)-2-trifluoromethyl-1,3-dioxolane (estimated by GC).

EXAMPLE 2 2-Methoxy-2-perfluoro-n-heptyl-1,3 -dioxolane (3) and2-(2-Chloroethoxy)-2-perfluoro-n-heptyl-1,3-dioxolane

    F(CF.sub.2).sub.7 CO.sub.2 CH.sub.2 CH.sub.2 Cl+CH.sub.3 ONa→3+4

2-Chloroethyl perfluorooctanoate was prepared by adding 162 g (0.375mol) of perfluorooctanoyl chloride to 32.2 g (0.40 mol) of2-chloroethanol cooled at 0° C., stirring the resulting mixture at 0°for 2 h, and then stirring for about 2.5 days at 25°. Fractionation ofthe resulting solution gave 152.6 g (85% yield) of the chloroethylester, b.p. 84°-88° at 1.3 kPa (10 mm), 98% pure by GC. IR (CCl₄): 2960(sat'd CH), 1790 (C═O), 1300-1100 cm⁻¹ (CF, C--O). NMR (CCl₄): ¹ H 4.59(t, J_(HH) 5.5 Hz, 2H, CH₂) and 3.70 ppm (t, J_(HH) 5.5 Hz, 2H, CH₂); ¹⁹F -81.6 (t of t, J_(FF) 10, 4 Hz, 3F, CF₃), -119.0 (t of t, J_(FF) 12, 6Hz, 2, F, CF₂ C═O), -122.4 (m, 4F, CF₂), -123.3 (m, 4F, CF₂), and -126.8ppm (m, 2F, CF₂).

2-Chloroethyl perfluorooctanoate (47.7 g, 0.10 mol) was added at 20° toa suspension of 4.8 g (0.10 mol) of 50% NaH in mineral oil in 100 mL ofdry DMSO, and 50 mL of diglyme were added. The resulting mixture wascooled to 10°; 3.2 g (0.10 mol) of methanol were added; and theresulting mixture was warmed. Evolution of gas commenced and becamebrisk. Cooling was required to keep the reaction temperature below 30°.The reaction mixture was stirred overnight and then poured into 500 mLof cold water, thereby causing a separation into layers. The lower layerwas washed with 200 mL of water, dried and distilled to give 11.4 g (27%yield) of by-product methyl perfluorooctanoate, b.p. 61°-70° at 2.7 kPa(20 mm); identified by IR and NMR spectra. Further fractionation gave13.0 g (28% yield) of crude 2-methoxy-2-perfluoro-n-heptyl-1,3-dioxolane(3), b.p. 75°-84° at 0.35 kPa (2.6 mm). A pure fraction, b.p. 79° at 2.6mm, was analyzed. IR (neat): 3000, 2960, 2920, and 2860 (sat'd CH),1250-1100 cm⁻¹ (CF, C--O). NMR (CCl₄): ¹ H 4.20 (s, 4H, ring OCH₂) and3.36 ppm (s, 3H,)CH₃); ¹⁹ F -81.6 (t of m, J_(FF) 9.5 Hz, 3F, CF₃),-122.0 (m, 2F, CF₂), -122.6 (m, 4F, CF₂), -123.3 (m, 4F, CF₂), and-126.8 ppm (m, 2F, CF₂).

Anal.: Calcd. for C₁₁ H₇ F₁₅ O₃ : C, 27.98, H, 1.50; F, 60.36; Found: C,28.28; H, 1.56; F, 61.11.

2-Chloroethoxy-2-perfluoro-n-heptyl-1,3-dioxolane (4) was also obtained,b.p. 70°-72.5° at 27 Pa (0.2 mm), 3.5 g (7% yield). IR (neat): 2980 and2920 (sat'd CH) and 1300-1100 cm⁻¹ (CF, C--O). NMR (CCl₄): ^(i) H 4.23(s, 4H, ring OCH₂), and 3.87 and 3.57 ppm (AA'BB'm, 4H, CH₂); ¹⁹ F -81.6(t of m, J_(FF) 10 Hz, 3F, CF₃), -121.8 (m, 2F, CF₂), -122.5 (m, 4F,CF₂), -123.2 (m, 4F, CF₂, and -126.8 ppm (m, 2F, CF₂).

Anal.: Calcd. for C₁₂ H₈ ClF₁₅ O₃ : C, 27.68; H, 1.55; Cl, 6.81. Found:C, 28.32; H, 1.69; Cl, 6.87.

EXAMPLE 3 2-Trifluoromethyl-1,3-dioxolane (5)

This example illustrates a process of the invention only. A suspensionof 9.6 g (0.20 mol) of 50% NaH in mineral oil in 150 mL of DMSO wasstirred at 15°-20° while 35.4 g (0.20 mol) of 2-chloroethyltrifluoroacetate were added dropwise. The resulting mixture was stirredovernight while the reaction temperature was maintained below 30°. Thereaction mixture was then heated to 50° at 0.33 kPa (2.5 mm) to driveoff volatile products which were recovered. Fractionation of thevolatiles gave 8.5 g (30% yield) of 2-trifluoromethyl-1,3-dioxolane,b.p. 87°-93°. IR (CCl₄): 3300 and 2910 (sat'd CH), 1200-1100 cm⁻¹ (CF,C--O). NMR (CCl₄): ¹ H 5.13 (q, J_(HF) 4 Hz, 1H, CH) and 4.07 ppm (s,4H, ring OCH₂).

Anal.: Calcd. for C₄ H₅ F₃ O₂ : C, 33.81; H, 3.55. Found: C, 33.68; H,3.39

EXAMPLE 4 2-Phenoxy-2-trifluoromethyl-1,3-doxolane (6)

    CF.sub.3 CO.sub.2 CH.sub.2 CH.sub.2 Cl+C.sub.6 H.sub.5 ONa→6

A solution of 23.5 g (0.25 mol) of phenol in 50 mL of DMSO was addeddropwise to a stirred suspension of 12.0 g (0.25 mol) of 50% NaH inmineral oil in 100 mL of DMSO maintained at 15°-20° by cooling. Afterevolution of gas had slowed, cooling and stirring were continued while44.3 g (0.25 mol) of 2-chloroethyl trifluoroacetate were added. Thetemperature of the reaction mixture was kept below 30° while theexotherm which occurred subsided, then the resulting mixture was stirredovernight, poured into 1 L of water, and extracted with 200 mL, then two100 mL portions, of ether. The resulting ether solutions were washedwith water, dried over CaSO₄, and distilled to give 27.6 g (47% yield)of 2-phenoxy-2-trifluoromethyl-1,3-dioxolane, b.p. 52°-54° at 80 Pa (0.6mm). IR (neat) and NMR (CCl₄) spectra were consistent with the assignedstructure.

Anal.: Calcd. for C₁₀ H₉ F₃ O₃ : C, 51.29; H, 3.87; F, 24.34. Found: C,51.19; H, 3.92; F, 24.49.

EXAMPLE 5 2-Trifluoromethyl-2-(2-phenoxytetrafluoroethyl)-1,3-dioxolane(7)

    C.sub.6 H.sub.5 ONa+CF.sub.2 ═CF.sub.2 +CF.sub.3 CO.sub.2 CH.sub.2 CH.sub.2 Cl→7

A suspension of 12.0 g (0.25 mol) of 50% NaH in mineral oil in 100 mL ofdry diglyme (diethylene glycol dimethyl ether) was stirred at 25° undernitrogen while a solution of 23.5 g (0.25 mol) of phenol in 50 mL ofdiglyme was added. The resulting mixture was stirred until evolution ofgas ceased, then charged into a 400 mL metal tube along with 44.3 g(0.25 mol) of 2-chloroethyl trifluoroacetate and 40 g (0.70 mol) oftetrafluoroethylene. The resulting mixture was agitated for 6 h whilethe temperature rose to 34° and subsided. Next the mixture was heated at50° for 6 h. The resulting reaction mixture was added to 1 L of water,thereby causing the formation of layers. The lower layer was separated,washed with water, dried over CaSO₄, and distilled to give 61.2 g (73%yield) of 2-trifluoromethyl-2-(2-phenoxytetrafluoroethyl)-1,3-dioxolane,b.p. 64°-67° at 13 Pa (0.1 mm). The IR (CCl₄) and NMR (CCl₄) spectra ofthe product were consistent with the structure assignment.

Anal.: Calcd. for C₁₂ H₉ F₇ O₃ : C, 43.13; H, 2.71; F, 39.80. Found: C,43.23; H, 2.75; F, 39.90.

EXAMPLE 6 2-(2-phenoxytetrafluoroethyl)-1,3-dioxolane (8)

    C.sub.6 H.sub.5 ONa+CF.sub.2 ═CF.sub.2 +HCO.sub.2 CH.sub.2 CH.sub.2 Cl→8

A suspension of 17.3 g (0.36 mol) of 50% NaH in mineral oil in 100 mL ofdiglyme was treated with a solution of 33.9 g (0.36 mol) of phenol in 50mL of diglyme. The resulting mixture was stirred overnight and thencharged into a 400 mL metal tube along with 38.6 g (0.36 mol) of2-chloroethyl formate and 40 g (0.40 mol) of tetrafluoroethylene. Theresulting mixture was agitated for 12 h, and then added to 1 L of coldwater, thereby causing the formation of layers. The lower layer waswashed with water, dried over CaSO₄, and distilled to afford 54.5 g (57%yield) of 2-(2-phenoxytetrafluoro-ethyl)-1,3-dioxolane, b.p. 62°-65° at8 Pa (0.06 mm). The IR (neat) and NMR (CCl₄) spectra of the product wereconsistent with the assigned sstructure.

Anal.: Calcd. for C₁₁ H₁₀ F₄ O₃ : C, 49.63; H, 3.79; F, 28.55. Found: C,49.90; H, 3.80; F, 28.91.

EXAMPLE 7 2,2'-Bi(2-[2-phenoxytetrafluoroethyl]-1,3-dioxolane) (9) and2-(2-Phenoxytetrafluoroethyl)-2-(2-chloroethoxycarbonyl)-1,3-dioxolane(10)

    (ClCH.sub.2 CH.sub.2 OCO--.sub.2 +C.sub.6 H.sub.5 ONa+CF.sub.2 CF.sub.2 →9+10

Bis(2-chloroethyl) oxalate was prepared by dropwise adding 95.1 g (0.75mol) of oxalyl chloride to 120.8 (1.50 mol) of 2-chloroethanolmaintained at 25°-30°. Reaction of these materials was continued overnight. The resulting product was distilled to give 150.0 g (93% yield)of bis(2-chloroethyl) oxalate, b.p. 93°-94° at 27 Pa (0.2 mm), m.p.41°-42°. The IR (CCl₄) and NMR (CCl₄) spectra of the product wereconsistent with the assigned structure.

Anal.: Calcd. for C₆ H₈ Cl₂ O₄ : C, 33.51; H, 3.75; Cl, 32.98. Found: C,33.51; H, 3.27; Cl, 32.71.

A suspension of 24.0 g (0.50 mol) of 50% NaH in mineral oil in 100 mL ofdiglyme was treated with a solution of 47.0 g (0.50 mol) of phenol in 50mL of diglyme. The resulting mixture was stirred overnight, and thencharged into a 400 mL metal tube along with 53.8 g (0.25 mol) ofbis(2-chloroethyl) oxalate and 50 g (0.50 mol) of tetrafluoroethylene.The resulting reaction mixture was agitated for 12 hr. and then shakenwith 1 L of cold water, after which layers formed. The lower layer,which was a mixture of solid and oil, was dissolved in 900 mL of etherto give an ether soluton which was dried over CaSO₄, filtered, andconcentrated to 200 mL. Addition of 50 mL of petroleum ether to theconcentrated ether solution caused precipitation of a crystallineproduct which was filtered off and rinsed to give 59.1 g of crystalline2,2'-bi(2-[ 2-phenoxytetrafluoroethyl]-1,3-dioxolane), m.p. 102°-103°.The filtrate was cooled to obtain a second crop of crystals, m.p.92°-97°, to give a total of 64.5 g (49% yield) of the bisketal. Ananalytical sample, m.p. 102.5°-103.5°, was obtained by recrystallizationof some of the product from tetrahydrofuran/petroleum ether mixedsolvent. The IR (KBr) and NMR (acetone-d₆) spectra of the product wereconsistent with the structure.

Anal.: Calcd. for C₂₂ H₁₈ F₈ O₆ : C, 49.82; H, 3.42; F, 28.66. Found: C,50.02; H, 3.47; F, 28.68.

The filtrate from the second crop of bisketal was evaporated to a heavyresidual oil having a mineral oil upper layer which was then removed.The remainder of the material was distilled through a molecular still toafford 21.0 g (23% yield) of2-(2-phenoxytetrafluoroethyl)-2-(2-chloroethoxycarbonyl)-1,3-dioxolane,b.p. 132°-135° at 8 Pa (0.06 mm), contaminated with a small amount ofmineral oil. An analytical sample was obtained by extraction of some ofthe product six times with petroleum ether, and the subjecting thecombined extract to reduced pressure (13 Pa, 0.1 mm) at 25°, after whichGC and ¹ H NMR indicated that the product was pure. IR (neat) and NMR(CCl₄) spectra for the product were consistent with the assignedstructure.

Anal.: Calcd. for C₁₄ H₁₃ ClF₄ O₅ : C, 45.12; H, 3.52; Cl, 9.51. Found:C, 45.40; H, 3.52; Cl, 9.21.

EXAMPLE 8 2-(2-Azidotetrafluoroethyl)-2-trifluoromethyl-1,3-dioxolane(11) and 2-Trifluoromethyl-2-cyanodifluoromethyl-1,3-dioxolane (12)

    A. NaN.sub.3 +CF.sub.2 ═CF.sub.2 +CF.sub.3 CO.sub.2 CH.sub.2 CH.sub.2 Cl→11

A 400 mL tube was charged with 16.3 g (0.25 mol) of sodium azide, 44.3 g(0.25 mol) of 2-chloroethyl trifluoroacetate, 150 mL of DMSO, and 40 g(0.40 mol) of tetrafluoroethylene, and then shaken for 8 h. Gasesevolving from the reaction mixture were bled off, and the resultingresidue was warmed under reduced pressure until only DMSO was beingvolitilized off. The volatiles were collected and then fractionated togive 20.1 g (45% recovery) of the starting 2-chloroethyltrifluoroacetate, b.p. 37°-39° at 3.3 kPa (25 mm), identified by IR,followed by 22.7 g of crude azide product, b.p. 44°-58° at 0.93 kPa (7.0mm). This crude product was washed twice with water, dried over CaSO₄,and distilled to give 14.8 g (21% conversion, 39% yield) of2-(2-azidotetrafluoroethyl)-2-trifluoromethyl-1,3-dioxolane, b.p.60°-61° at 1.25 kPa (9.4 mm), GC pure. IR (CCl₄) and NMR (CCl₄) spectraof the product were consistent with the assigned structure.

    B. N.sub.3 CF.sub.2 CF.sub.2 C(ONa)(OCH.sub.2 CF.sub.3)CF.sub.3 +ClCH.sub.2 CH.sub.2 OH→11

A 400 mL metal tube was charged with 32.5 g (0.50 mol) of sodium azide,98.0 (0.50 mol) of trifluoroethyl trifluoroacetate, 150 mL of DMSO, and50 g (0.50 mol) of tetrafluoroethylene, and then shaken for 6 h withoutheating and then one h at 40°. A total of three such reactions were run,and the resulting solutions of intermediate salt were combined.

The combined solutions of intermediate salt were stirred at 25°-30°while 129 g (1.6 mol) of 2-chloroethanol were added dropwise. Theresulting reaction mixture was stirred for 4 h after the addition hadbeen completed. Another 32 g (0.40 mol) of 2-chloroethanol were added,and the resulting mixture was stirred overnight. Next, the mixture waspoured into 1 L of cold water, causing separation into layers. The lower(organic) layer (390 g) was separated. The aqueous layer was extractedwith 500 mL of ether, and the combined organic layers were washed with300 mL of water and dried over CaSO₄. GC analysis indicated that thesolution contained 37% of2-(2-azidotetrafluoroethyl)-2-trifluoromethyl-1,3-dioxolane. Theidentity of this product was confirmed by adding the ether solution overa period of 1.5 hr to a solution of 393 g (1.5 mol) oftriphenylphosphine in 1 L of ether while the triphenylphosphine solutionwas stirred under a water-cooled condenser. The resulting mixture wasstirred an additional 0.5 H, during which time vigorous evolution of N₂and the accompanying exotherm abated. The mixture was filtered, and theresulting solids were rinsed with ether. The filtrate was concentratedand its volatiles content were collected under reduced pressure and theresulting volatiles were collected and fractionated to give 193 g (59%yield from tetrafluoroethylene) of2-trifluoromethyl-2-cyanodifluoromethyl-1,3-dioxolane (12), b.p. 64°-66°at 6.6 kPa (50 mm).

EXAMPLE 9 2-Methoxy-2-(2-methoxyetetrafluoroethyl)-1,3-dioxolane (13)and 2-(2-Chloroethoxy)-2-(2-methoxy-tetrafluoroethyl)-1,3-dioxolane (14)

    A. CH.sub.3 OCF.sub.2 CF.sub.2 CO.sub.2 CH.sub.3 +ClCH.sub.2 CH.sub.2 OH+NaH→13+14

A mixture of 95.0 g (0.50 mol) of methyl 3-methoxytetrafluoropropionate,24 g (0.50 mol) of 50% NaH in mineral oil, and 500 mL of THF was stirredat -20° while 40.3 g (0.50 mol) of 2-chloroethanol were added dropwise.The resulting mixture was stirred at -20° while hydrogen evolution(abated in 15 min), and then at about 30° until the ensuing exothermsubsided (about 2-3 h). The mixture was filtered, and solvents weredistilled from the resulting filtrate. The residue was added to 700 mLof water, causing separation into layers. The lower layer was dried overanhydrous Na₂ CO₃, and distilled to give 30.4 g (32%) of recoveredester, b.p. 30°-32° at 5.3 kPa (40 mm), identified by IR, and 18.0 g ofa mixture of products, b.p. 40°-50° at 20 Pa (0.15 mm). Fraction of themixture of products gave 10.6 g (9% yield) of2-methoxy-2-(2-methoxytetrafluoroethyl)-1,3-dioxolane, b.p. 50°-55° at20 Pa (0.15 mm). IR (neat) and NMR (CCl₄) spectra of the product wereconsistent with the structure.

Anal.: Calcd. for C₇ H₁₀ F₄ O₄ : C, 35.91; H, 4.30; F, 32.46. Found: C,35.90; H, 4.33; F, 32.49.

By-product2-(2-chloroethoxy)-2-(2-methoxytetrafluoroethyl)-1,3-dioxolane, b.p.80°-83° at 66.5 Pa (0.5 mm), was also obtained as 2.6 g (2% conversion)of oil containing minor impurities. IR (neat) and NMR (CCl₄) wereconsistent with the structure.

Anal.: Calcd. for C₈ H₁₁ ClF₄ O₄ : C, 34.00; H, 3.92; Cl, 12.55. Found:C, 34.75; H, 3.84; Cl, 11.09.

    B. CH.sub.3 OCF.sub.2 CF.sub.2 C(ONa)(OCH.sub.3).sub.2 +ClCH.sub.2 CH.sub.2 OH→20

A solution of 95.0 g (0.50 mol) of methyl 3-methoxytetrafluoropropionatein 500 mL of DMSO was stirred at 15°-20° while 27.0 g (0.50 mol) ofsodium methoxide were added portionwise. The resulting mixture wasstirred until the sodium methoxide had dissolved (10 min), after which40.3 g (0.50 mol) of 2-chloroethanol were added dropwise at 20°-25°. Theresulting reaction mixture was stirred for 4 h after completion of theaddition. Then, 13.5 g (0.25 mol) of sodium methoxide were added at15°-20°, and 20.2 g (0.25 mol) of 2-chloroethanol were added dropwise.The resulting mixture was stirred for 1 hr and then poured into 2 L ofwater, thereby causing separation into layers. The lower layer waswashed with 200 mL of water, dried over CaSO₄, filtered, and distilledto give 14.3 g (15%) of recovered ester, b.p. 58°-60° at 4.0 kPa (30mm), followed by 56.8 g (58% yield) of2-methoxy-2-(2-methoxytetrafluoroethyl)-1,3-dioxolane, b.p. 70°-71° at0.19 kPa (1.4 mm). The latter product was identified by comparison ofits IR spectrum to that of the product from part A of this Example.

EXAMPLE 10 2-Methoxy-2-(2-methoxycarbonyltetrafluoroethyl)-1,3-dioxolane(15) and2-(2-chloroethoxy)-2-(2-methoxycarbonyltetrafluoroethyl)-1,3-dioxolane(16)

    CH.sub.3 OC(O)CF.sub.2 CF.sub.2 C(O)OCH.sub.3 +ClCH.sub.2 CH.sub.2 OH+NaH→15+16

A mixture of 43.6 g (0.20 mol) of dimethyl tetrafluorosuccinate, 16.1 g(0.20 mol) of 2-chloroethanol, and 100 mL of DMSO was stirred andmaintained at 25°-35° while 9.6 g (0.20 mol) of 50% NaH in mineral oilwere added portionwise. The resulting mixture was stirred overnight, andthen poured into 500 mL of cold water. Ether (300 mL) was added, and theresulting mixture was shaken. After mixture separated into layers, theether layer was separated, washed with 100 mL of water, dried overCaSO₄, filtered and distilled to give 23.1 g (44%) of2-methoxy-2-(2-methoxycarbonyltetrafluoroethyl)-1,3-dioxolane, b.p.72°-72.5° at 13 Pa (0.1 mm). IR (neat) and NMR (CCl₄) spectra of theproduct were consistent with the assigned structure.

Anal.: Calcd. for C₈ H₁₀ F₄ O₅ : C, 36.65; H, 3.85; F, 28.99. Found: C,36.45; H, 3.95; F, 28.70.

Further fractionation gave 5.9 g of crude2-(2-chloroethoxy)-2-(2-methoxycarbonyltetrafluoroethyl)-1,3-dioxolane,b.p. 97°-102° at 13 Pa (0.1 mm), which crystallized on standing. Thecrystals were washed with petroleum ether to give 4.6 g (7% yield) ofthe product, m.p. 38°-39°. An analytical sample was obtained byrecrystallization of a portion of the product from a mixture of etherand petroleum ether, m.p. 38°-39°. IR (CCl₄) and NMR (CCl₄) spectra ofthe product were consistent with the assigned structure.

Anal.: Calcd. for C₉ H₁₁ ClF₄ O₅ : C, 34.80; H, 3.57; Cl, 11.41. Found:C, 34.87; H, 3.59; Cl, 11.52.

EXAMPLE 11 2-Methoxy-2-cyanodifluoromethyl-1,3-dioxolane (17) and2-(2-Chloroethoxy)-2-cyanodifluoromethyl-1,3-dioxolane (18)

    NCCF.sub.2 CO.sub.2 CH.sub.3 +ClCH.sub.2 CH.sub.2 OH+NaH→17+18

A mixture of 27.0 g (0.20 mol) of methyl cyanodifluoroacetate, 16.1 g(0.20 mol) of 2-chloroethanol, and 100 mL of DMSO was maintained at25°-30° and stirred while 9.6 g (0.20 mol) of 50% NaH in mineral oilwere added portionwise. The resulting mixture was stirred for 6.5 hr,and then distilled at 1.6 mm until 100 mL of distillate had been taken.The distallate was poured into 250 mL of cold water, and the resultingmixture was extracted with 100 mL, and then 50 mL, of ether. Thecombined ether layers were washed with 50 mL of water, dried over CaSO₄,filtered and distilled to give 10.5 g (29% yield) of2-methoxy-2-cyanodifluoromethyl-1,3-dioxolane, b.p. 65° at 0.40 kPa (3mm). IR (neat) and NMR (CCl₄) spectra of the product were consistentwith the assigned structure.

Anal.: Calcd. for C₆ H₇ F₂ NO₃ : C, 40.23; H, 3.94; F, 21.21; N, 7.82.Found: C, 40.30; H, 3.88; F, 20.95; N, 7.72.

The residual higher-boiling reaction mixture was mixed with 250 mL ofice-water and extracted with 100 mL, then 50 mL, of ether. The combinedether layers were washed with 50 mL of water, dried over CaSO₄,filtered, and distilled to give 3.7 g (7% yield) of2-(2-chloroethoxy)-2-cyanodifluoromethyl-1,3-dioxolane, b.p. 58° at 66.5Pa (0.5 mm). An analytical sample of the product was obtained byextraction of a portion of the product with 5 aliquots of petroleumether to remove a small amount of mineral oil and then subjecting thematerial to reduced pressure of 66.5 Pa (0.5 mm) to eliminate residualpetroleum ether. IR (neat) and NMR (CCl₄) spectra of the product wereconsistent with the assigned structure.

Anal.: Calcd. for C₇ H₈ ClF₂ NO₃ : C, 36.94; H, 3.54; N, 6.15. Found: C,37.20; H, 3.93; N, 6.41.

EXAMPLE 12 2,2-Bis(methoxycarbonyldifluoromethyl)-1,3-dioxolane (19)##STR20##

A mixture of 61.5 g (0.25 mol) of dimethyltetrafluoroacetone-1,3-dicarboxylate, 20.1 g (0.25 mol) of2-chloroethanol, and 50 mL of pentane was stirred at 20° while 38 g(0.28 mol) of anhydrous K₂ CO₃ were added portionwise over a 15-minperiod. Next, ether was added and stirring was continued for 1 day. Theresulting mixture was filtered, and the resulting filtrate wasevaporated to give a mixture from 2:1 ether/pentane mixed solvent gave10.3 g of solid, m.p. 61°-65°. Extraction of the filter cake with 100 mLof ether gave another 4.2 g, m.p. 62°-65°, for a total of 14.5 g ofcrude product. Recrystallization of the crude product from ether/hexanemixed solvent gave 11.1 g (15% yield) of2,2-bis(methoxycarbonyldifluoromethyl)-1,3-dioxolane, m.p. 66.5°-67.5°.A sample sublimed at 60° and 27 Pa (0.2 mm) was analyzed. IR (KBr) andNMR (acetone-d₆) of the product were consistent with the assignedstructure.

Anal.: Calcd. for C₉ H₁₀ F₄ O₆ : C, 37.25; H, 3.47. Found: C, 37.11; H,3.55.

EXAMPLE 13 2-(2-Azidotetrafluoroethyl)-2-trifluoromethyl)dioxolane (20a)and 2-trifluoromethyl-2-cyanodifluoromethyl-1,3-dioxolane (20)

A solution of 103.4 g (0.43 mol) of 4-azidoperfluorobutanone-2 in 100 mLof THF was stirred in a container placed in an ice-bath while 40.5 g(0.50 mol) of 2-chloroethanol were added. The resulting mixture wasadded dropwise to a stirred suspension of 24.0 g (0.50 mol) of 50% NaHin mineral oil in 150 mL of THF while the temperature was maintained at20°-25°. The mixture was stirred overnight. About 200 mL of solvent wasdistilled off at b.p. of 32°-36° and 33.25 kPa (250 mm), and theresulting residue was added to 500 mL of water, causing layers to form.The lower layer was separated, dried over CaSO₄, filtered and distilledto give 80.6 g (66%) of2-(2-azidotetrafluoroethyl)-2-trifluoromethyl-1,3-dioxolane. b.p.59°-60° at 1.25 kPa (9.4 mm), and identified by GC and IR.

A solution of 26.3 g (0.10 mol) of triphenylphosphine in 150 mL of etherwas stirred while 28.3 g (0.10 mol) of the azidodioxolane preparedpursuant to the foregoing paragraph were added rapidly. A mild exothermensued and was accompanied by gas evolution and yellowing. The resultingmixture was stirred for 4 days, filtered and distilled to give 19.7 g(91% yield) of 2-trifluoromethyl-2-cyanodifluoromethyl-1,3-dioxolane,b.p. 67°-68.5° at 6.65 kPa (50 mm). IR (neat) and NMR (CCl₄) spectra forthe product were consistent with the assigned structure.

Anal.: Calcd. for C₆ H₄ F₅ NO₂ : C, 33.20; H, 1.86; N, 6.45. Found: C,33.68; H, 2.03; N, 6.31.

EXAMPLE 14 2,2'-Bi(2-trifluoromethyl-1,3-dioxolane) (21) and2-Trifluoromethyl-2-trifluoroacetyl-1,3-dioxolane (22)

    CF.sub.3 C(O)C(O)CF.sub.3 +ClCH.sub.2 CH.sub.2 OH+NaH→21+22

A mixture of 44.0 g (0.23 mol) of hexafluorobiacetyl, 37.0 (0.46 mol) of2-chloroethanol, and 150 mL of DMSO was stirred at 15°-20° while 22.1 g(0.46 mol) of 50% NaH in mineral oil were added portionwise. Theresulting reaction mixture was then stirred at 20°-25° for one day andthen added to 1 L of water. The resulting mixture was extracted with400, then two 100 mL aliquots, of ether. The ether extracts were washedwith 100 mL of water, dried over CaSO₄, and the solvent was distilledoff. The resulting residue was titrated with 50 mL of petroleum ether,and the resulting solid was recrystallized from a 2:1 mixture ofpetroleum ether and ether to give 18.8 g of2,2'-bi(2-trifluoromethyl-1,3-dioxolane), m.p. 88°-90°. A second crop,7.3 g, m.p. 86°-89°, was obtained by cooling the remaining supernatantwhich was then filtered to remove this crop. Evaporation of the filtrateand sublimation of the residue at 85° and 0.66 kPa (5 mm) gave another2.8 g, m.p. 85°-88°, for a total of 28.9 g (45% yield) of thebi(dioxolane) product. An analytical sample, m.p. 88°-90°, was obtainedby recrystallization from petroleum ether/ether mixed solvent. IR (CCl₄)and NMR (CCl₄) spectra for the product were consistent with the assignedstructure.

Anal.: Calcd. for C₈ H₈ F₆ O₄ : C, 34.06; H, 2.86; F, 40.40. Found: C,33.91; H, 2.85; F, 40.16.

Volatiles collected in a -80° trap during the sublimation were 7.9 g(about 13%) of partially hydrated2-trifluoromethyl-2-trifluoroacetyl-1,3-dioxolane. A sample of thismaterial was exposed to moist air until its m.p. rose to a constantvalue, giving a pure sample of2-trifluoromethyl-2-trifluoroacetyl-1,3-dioxolane monohydrate, m.p.102°-103°. IR (CD₃ CN) and NMR (CD₃ CN) spectra of the product wereconsistent with the assigned structure.

Anal.: Calcd. for C₆ H₆ F₆ O₄ : C, 28.14; H, 2.36; F, 44.51. Found: C,28.04; H, 2.35; F, 44.20.

EXAMPLE 15 2,2-Bis(2-methoxytetrafluoroethyl)-1,3-dioxolane (23)

A mixture of 58 g (about 0.2 mol) of crudebis(2-methoxytetrafluoroethyl)ketone, 16.9 g (0.21 mol) of2-chloroethanol, and 50 mL of ether was stirred while 29.0 g (0.21 mol)of anhydrous K₂ CO₃ were added in portions with cooling. The resultingreaction mixture was stirred overnight, filtered and distilled to give40.7 g of 2,2-bis(2-methoxytetrafluoroethyl)-1,3-dioxolane, b.p. 81° at40 Pa (0.3 mm), m.p. 30°-40°. Dissolution of the resulting filter cakein water, filtration of the resulting mixture and drying gave another8.5 g of product, m.p. 38.5°-40°, for a total yield of 49.2 g (74%). IR(CCl₄) and NMR (CCl₄) of the product were consistent with the assignedstructure.

Anal.: Calcd. for C₉ H₁₀ F₈ O₄ : C, 32.35; H, 3.02; F, 45.48. Found: C,32.14; H, 3.19; F, 45.22.

EXAMPLE 162-Trifluoromethyl-2-(3-methoxycarbonylperfluoro-2-oxabutyl)-1,3-dioxolane(24) ##STR21##

A mixture of 64.4 g (0.20 mol) of methyl4-keto-2-trifluoromethylhexafluoro-2-oxahexanoate, 16.1 g (0.20 mol) of2-chloroethanol, and 100 mL of pentane was stirred with 37.6 g (0.20mol) of anhydrous K₂ CO₃. Reaction of the starting materials was slow,so 50 mL of ether were added, and the reaction mixture was stirredovernight. The resulting solid mass was titrated thoroughly with 500 mLof ether, filtered and distilled to give 25.9 g 935% yield) of2-trifluoromethyl-2-(3-methoxycarbonylperfluoro-2-oxabutyl)-1,3-dioxolane,b.p. 68°-70° at 0.29 kPa (2.2 mm). IR (CCl₄) and NMR (CCl₄) spectra ofthe product were consistent with the assigned structure.

Anal.: Calcd. for C₉ H₇ F₉ O₅ : C, 29.52; H, 1.93; F, 46.70. Found: C,29.75; H, 2.11; F, 46.41.

EXAMPLE 17 2-Trifluoromethyl-2-pentafluoroethyl-1,3-dioxolane (25)

    KF+CF.sub.2 ═CF.sub.2 +CF.sub.3 CO.sub.2 CH.sub.2 CH.sub.2 Cl→25

A mixture of 29.1 g (0.50 mol) of dry potassium fluoride, 88.3 g (0.50mol) of 2-chloroethyl trifluoroacetate, 150 mL of dimethylsulfoxide, and50 g (0.50 mol) of tetrafluoroethylene was shaken in a 400-mL metal tubeat 75° for 18 h. Volatile products were transferred from the reactionmixture held at 43° (1.2 mm). These volatiles were stirred with 500 mLof 10% aqueous NaOH to remove unreacted ester and a small amount ofdimethylsulfoxide, then fractionated to afford 61.6 g (47%) of2-trifluoromethyl-2-pentafluoroethyl-1,3-dioxolane, b.p. 118°-120°. IR(CCl₄) and NMR (CCl₄) spectra for the product were consistent with theassigned structure.

Anal.: Calcd. for C₆ H₄ F₈ O₂ : C, 27.71; H, 1.55; F, 58.44. Found: C,27.57; H, 1.65; F, 58.40.

EXAMPLE 18 2-Trifluoromethyl-2-trichloromethoxytetrachloro-1,3-dioxolane(26) and 2-Trifluoromethylpentachloro-1,3-dioxolane (27) ##STR22##

A mixture of 25.8 g (0.15 mol) of2-methoxy-2-trifluoromethyl-1,3-dioxolane prepared pursuant to aprocedure similar to that of Example 1 and 80 mL of CCl₄ was stirred ina container equipped with a condenser maintained at -80° while chlorinewas bubbled in rapidly enough to maintain the resulting reaction mixtureat 65°-70° due to the exothermic reaction. Two h later when the reactionhad slowed, sunlamp irradiation was commenced with the continuedaddition of chlorine. After another 7.75 h, the reaction was completed.Distillation of the reaction mixture gave 12.2 g (26% yield) of2-trifluoromethylpentachloro-1,3-dioxolane, b.p. 55°-57° at 1.3 kPa (10mm). The GC, IR and ¹⁹ F NMR spectra of the product were consistent withthe assigned structure. Further fractionation of the remaining reactionmixture gave 33.9 g (55% yield) of2-trifluoromethyl-2-trichloromethoxytetrachloro-1,3-dioxolane, b.p.55°-57° at 27 Pa (0.2 mm).

Anal.: Calcd. for C₅ Cl₇ F₃ O₃ : C, 14.53; Cl, 60.06; F, 13.79. Found:C, 14.46; Cl, 58.94; F, 14.05.

EXAMPLE 192-(2-Trichloromethoxycarbonyltetrafluoroethyl)pentachloro-1,3-dioxolane(28) ##STR23##

2-Methoxy-2-(2-methoxycarbonyltetrafluoroethyl)-1,3-dioxolane (73.2 g,0.28 mol) prepared similarly to the procedure in Example 18 was stirredin a container equipped with a condenser maintained at -80° andirradiated with sunlamp while chlorine was passed in at a ratesufficient to cause the temperature of the resulting mixture to risefrom 50° to 80° over a 30-h period. Evaporation of volatiles from theresulting crude product gave 144 g of oil, which was indicated by ¹⁹ FNMR to be mainly2-(2-trichloromethoxycarbonyltetrafluoroethyl)pentachloro-1,3-dioxolane.

EXAMPLE 202-(2-Methoxycarbonyltetrafluoroethyl)-4,5-dichloro-2,4,5-trifluoro-1,3-dioxolane(29) and2-(2-Methoxycarbonyltetrafluoroethyl)-4,4,5-trichloro-2,5-difluoro-1,3-dioxolane(30)

A mixture of 144 g (about 0.28 mol) of crude2-(2-trichloromethoxycarbonyltetrafluoroethyl)pentachloro-1,3-dioxolaneprepared similarly to the procedure given in Example 19, 100 g (0.56mol) of flame-dried SbF₃, and 2 mL of SbCl₅ was stirred and heated. Gas(COCl₂) evolution was noticed at 50°-60° during an initial exotherm. Theresulting mixture was stirred at 100° for 1 h, after which time 23 mL ofliquid had been collected in a -80° trap. The mixture was then refluxedfor 1 h while the reactor temperature fell from 119° to 101°. Volatiles(81 g) transferred by warming the reaction mixture at 13 Pa (0.1 mm)were fractionated to give 44.2 g of product, b.p. 103° at 101 kPa (1atm) to 51° at 1.3 kPa (10 mm). A fraction, b.p. 65°-68° at 13 kPa (100mm), was shown by IR and ¹⁹ F NMR to be2-(2-fluorocarbonyltetrafluoroethyl)-4,5-dichloro-2,4,5-trifluoro-1,3-dioxolane(29a). Another fraction, b.p. 56°-56.5° at 2.7 kPa (20 mm), was shown byGC, IR and ¹⁹ F NMR to contain2-(2-chlorocarbonyltetrafluoroethyl)-4,5-dichloro-2,4,5-trifluoro-1,3-dioxolane(29b). Still another fraction, b.p. 47°-51° at 10 mm, was shown by GC,IR, and ¹⁹ F NMR to contain2-(2-chlorocarbonyltetrafluoroethyl)-4,4,5-trichloro-2,5-difluoro-1,3-dioxolane(30a).

The combined acid fluorides and chlorides (44 g, about 0.12 mol) whosepreparation was described in the preceding paragraph were added dropwiseto 19.2 g (24 mL, 0.6 mol) of methanol. The resulting mixture wasstirred briefly and distilled to give 20.4 g of2-(2-methoxycarbonyltetrafluoroethyl)-4,5-dichloro-2,4,5-trifluoro-1,3-dioxolane(29) containing some dimethyl tetrafluorosuccinate impurity, b.p.46°-61° at 0.50 kPa (3.8 mm). The GC, IR and NMR spectra of the productwere consistent with the assigned structure. Further distillation gave6.7 g of2-(2-methoxycarbonyltetrafluoroethyl)-4,4,5-trichloro-2,5-difluoro-1,3-dioxolane(30), b.p. 70°-75° at 0.50 kPa (3.8 mm). IR (CCl₄) and NMR (CCl₄)-¹⁹ Fspectra were consistent with the assigned structure.

Anal.: Calcd. for C₇ H₃ Cl₃ F₆ O₄ : C, 22.63; H, 0.81; Cl, 28.63; F,30.69. Found: C, 22.71; H, 0.79; Cl, 28.31; F, 30.72.

Anal. Calcd. for C₇ H₃ Cl₃ F₆ O₄ : C, 22.63; H, 0.81; Cl, 28.63; F,30.69. Found: C, 22.71; H, 0.79; Cl, 28.31; F, 30.72.

EXAMPLE 212,2-Bis(2-trichloromethoxytetrafluorethyl)-4,4,5,5-tetrachloro-1,3-dioxolane(31) ##STR24##

A solution of 668 g (2.0 mol) of2,2-bis(2-methoxy-tetrafluoroethyl-1,3-dioxolane in 1300 mL of CCl₄ wasstirred and irradiated at 60°-70° for 25 h, then at 70°-80° for 9 h,while chlorine was bubbled in the entire time. Solvent was distilledoff, and the resulting residue was heated at 80° at 0.3 mm to give 1330g (98% yield) of nearly pure2,2-bis(2-trichloromethoxytetrafluoroethyl)-4,4,5,5-tetrachloro-1,3-dioxolaneas a heavy oil. ¹ H NMR showed no proton present. IR, ¹⁹ F NMR and ¹³ CNMR spectra of the product confirmed the structure.

EXAMPLE 222-(2-Trichloromethoxytetrafluoroethyl)pentachloro-1,3-dioxolane (32)##STR25##

2-Methoxy-2-(2-methoxytetrafluoroethyl)-1,3-dioxolane (47 g, 0.20 mol)was stirred for 45 min while chlorine was bubbled in and a mild exothermoccurred. Addition of chlorine was continued and irradiation with asunlamp was started. Reaction was continued for 25 h with thetemperature slowly raised from 60°-90°. Fractionation of the reactionmixture was accompanied by slow decomposition, so that distillation wasstopped after 30.9 g of crude product, b.p. 77.5°-79° at 13 Pa (0.1 mm),were obtained. The resulting distillate was stirred with excess 10%aqueous NaOH and washed with water to give 13.6 g of2-(2-trichloromethoxytetrafluoroethyl)pentachloro-1,3-dioxolane as apale yellow oil. IR (neat): no C═O. NMR (CCl₄): ¹ H none; ¹⁹ F and ¹³ Cspectra were consistent with the assigned structure.

Anal.: Calcd. for C₆ Cl₈ F₄ O₃ : C, 15.02; Cl, 59.13; F, 15.84. Found:C, 14.74; Cl, 59.12; F, 15.49.

EXAMPLE 23 Fluorination of2-Trifluoromethyl-2-trichloromethoxytetrachloro-1,3-dioxolane

This Example illustrates a use of a product of the invention.

A mixture of 84 g (0.20 mol) of2-trifluoromethyl-2-trichloromethoxytetrachloro-1,3-dioxolane preparedby a procedure similar to that given in Example 18 and 89.4 g (0.50 mol)of SbF₃ evolved gas vigorously when 5 mL of SbCl₅ was added. Afterreaction had subsided, the resulting mixture was heated at 75° for 30min, then at 100° for 1 h, then at reflux for 4 h. Liquid products weretransferred under reduced pressure and shown by GC to consist of 96.5%of a mixture of 16.7 g (32% yield) of2-trifluoromethyl-4,5-dichloro-2,4,5-trifluoro-1,3-dioxolane and 33.4 g(59% yield) of2-trifluoromethyl-4,4,5-trichloro-2,5-difluoro-1,3-dioxolane.

EXAMPLE 242-Trifluoromethyl-2-cyanodifluoromethyltetrachloro-1,3-dioxolane (33)##STR26##

A mixture of 193 g (0.89 mol) and2-trifluoromethyl-2-cyanodifluoromethyl-1,3-dioxolane and 400 ml of CCl₄was stirred and irradiated with a sunlamp while chlorine was bubbled inat 60°-70° for 14.5 hr. Distillation of the resulting reaction mixturegave 255.3 g (81%) of2-trifluoromethyl-2-cyanodifluoromethyltetrachloro-1,3-dioxolane, b.p.58°-59° at 1.3 kPa (10 mm). IR (neat) and NMR-¹⁹ F spectra of theproduct were consistent with the assigned structure.

Anal.: Calcd. for C₆ Cl₄ F₅ NO₂ : C, 20.31; Cl, 39.96; N, 3.95. Found:C, 20.18; Cl, 40.25; N, 3.74.

EXAMPLE 252-Trifluoromethyl-2-cyanodifluoromethyl-4,5-dichloro-4,5-difluoro-1,3-dioxolane(34) and2-Trifluoromethyl-2-cyanodifluoromethyl-4,4,5-trichloro-5-fluoro-1,3-dioxolane(35) ##STR27##

A mixture of 47.2 g (0.13 mol) of2-trifluoromethyl-2-cyanodifluoromethyltetrachloro-1,3-dioxolaneprepared by a procedure similar to that given in Example 24, 35.8 g(0.20 mol) of SbF₃, and 1 mL of SbCl₅ was stirred at 100° for 5 hr andat 120° for 6 h. Volatiles were removed under reduced pressure anddistilled to give 10.4 g (25%) of2-trifluoromethyl-2-cyanodifluoromethyl-4,5-dichloro-4,5-difluoro-1,3-dixolane,b.p. 56°-65° at 13.3 kPa (100 mm). IR (CCl₄) and NMR (CCl₄)-¹⁹ F spectrawere consistent with the assigned structure.

Anal.: Calcd. for C₆ Cl₂ F₇ NO₂ : C, 22.38; Cl, 22.02; N, 4.35. Found:C, 22.50; Cl, 22.31; N, 4.20.

Further distillation gave 24.6 g (56%) of2-trifluoromethyl-2-cyanodifluoromethyl-4,4,5-trichloro-5-fluoro-1,3-dixolane,b.p. 53°-54° at 3.3 kPa (25 mm). IR (CCl₄) and NMR (CCl₄)-¹⁹ F spectraof this produce were consistent with the assigned structure.

Anal.: Calcd for C₆ Cl₃ F₆ NO₂ : C, 21.29; Cl, 31.43; N, 4.14. Found: C,21.33; Cl, 31.52; N, 3.67.

EXAMPLE 262-Trifluoromethyl-2-cyanodifluoromethyl-4-chloro-5-fluoro-1,3-dioxole(36) ##STR28##

Zinc dust (39.2 g, 0.60 mol) was warmed under vacuum, then blanketedwith nitrogen, evacuated, and the process repeated once more. To thezinc dust blanketed with nitrogen were added 250 mL of dry diglyme, 5.0g (0.02 mol) of iodine, and 3.0 g (0.02 mol) of NaI. The resultingmixture was stirred under N₂ until the iodine reacted, and then 73.9 g(0.22 mol) of2-trifluoromethyl-2-cyanodifluoromethyl-4,4,5-trichloro-5-fluoro-1,3-dioxolanewere added. The resulting reaction mixture was stirred at 100° for 2 h,after which volatiles were transferred by warming the mixture to 70° at0.53 kPa (4 mm) pressure. The volatiles were dried over CaSO₄, filteredand distilled to give 29.8 g (51% yield) of2-trifluoromethyl-2-cyanodifluoromethyl-4-chloro-5-fluoro-1,3-dioxole,b.p. 59°-62° (33.2 kPa, 250 mm). IR (CCl₄) and NMR (CCl₄): ¹ H none; ¹⁹F spectra of the product were consistent with the assigned structure.

Anal.: Calcd. for C₆ ClF₆ NO₂ : C, 26.94; Cl, 13.25; N, 5.24. Found: C,26.74; Cl, 13.51; N, 4.98.

The early fractions contained appreciable amounts of the 4-hydrodioxole,giving rise to IR spectra containing bands at 3190 (unsat'd) CH) and1775 cm⁻¹ (C═C) for this monomer.

EXAMPLE 27 Copolymer of2-Trifluoromethyl-2-cyanodifluoromethyl-4-chloro-5-fluoro-1,3-dioxolewith Tetrafluoroethylene

A 75 mL metal tube charged with 10 g (about 0.037 mol) of2-trifluoromethyl-2-cyanodifluoromethyl-4-chloro-5-fluoro-1,3-dioxolecontaining 20% of the corresponding 4-hydrodioxole, 17 mL of CFCl₂ CF₂Cl, 2 mL of 3% perfluoropropionyl peroxide in CFCl₂ CF₂ Cl, and 20 g(0.20 mol) of tetrafluoroethylene was shaken at 40° for 8 h. Theresulting mixture was evaporated at 60° and 23 Pa 0.2 mm pressure togive copolymer, which was stirred with 100 mL of ether, filtered, rinsedwell, and dried under reduced pressure. The resulting solid whitecopolymer, 2.7 g, softened and melted at 260°-280° on a melting pointblock. IR (nujol): 2260 cm⁻¹ (C═N).

Anal.: Calcd. for 4-chlorodioxole.16.8CF₂ ═CF₂ : N, 0.72. Found: N,0.72, 0.71.

IR analysis of the recovered monomers showed no change in ratio of4-chloro- and 4-hydrodioxoles.

EXAMPLE 282-Trifluoromethyl-2-cyanodifluoromethyl-4,5-difluoro-1,3-dioxole (37)##STR29##

A flask containing 15.0 g (0.63 mol) of magnesium turnings, 0.2 g ofmercuric chloride, and 0.2 g of iodine was evacuated to remove air andmoisture, then blanketed with nitrogen. Sodium-dried THF, 200 mL, wasadded, and the resulting mixture was heated to reflux. While the mixturewas stirred and refluxed, 32.2 g (0.10 mol) of2-trifluoromethyl-2-cyanodifluoromethyl-4,5-dichloro-4,5-difluoro-1,3-dioxolanewere added dropwise over 1.25 h and distillate was taken at 3 times therate of addition. Methyl iodide (0.1 ml) was injected near the beginningto insure start of reaction. After the addition had been completed,another 25 mL of distillate were taken for a total of 125 mL. Thedistillate was added to 500 mL of water, and the resulting lower layerwas separated, washed with 10 mL of water to give 2.0 g of liquid. GCindicated the presence of 0.7 g (2%) of2-trifluoromethyl-2-cyanodifluoromethyl-4,5-difluoro-1,3-dioxole alongwith starting dioxolane and a trace of2-trifluoromethyl-2-cyanodifluoromethyl-4-chloro-5-fluoro-1,3-dioxole.The identity of the product was confirmed by IR (CCl₄): 1890 cm⁻¹ (C═C).

The invention being claimed is:
 1. A process for preparing a dioxolaneof the formula ##STR30## wherein: R_(F) is a perfluorinated alkyl grouphaving 1 to 14 carbon atoms and terminally substituted with --F, --Cl,--OR, --OC₆ F₅, --SR', --SO₂ R', --SO₂ F, --N₃, --CN or --C(O)OR', orsaid perfluorinated alkyl group also containing ether oxygen;R' is analkyl group of 1 to 4 carbon atoms; R is an alkyl group of 1 to 4 carbonatoms, --CH₂ CF₃ or --C₆ H₅ ; Y is --H, --OR or --CF₂ CF₂ Z; and Z is--F, --N₃, --OC₆ H₅, --SR' or --OC₆ F₅ ;comprising contacting at atemperature of from about -20° C. to about 80° C. a 2-chloro- or2-bromoethyl fluoroalkyl carboxylate having the formula R_(F) CO₂ CH₂CH₂ X with a compound of the formula MY¹ in a suitable solvent; whereinY¹ is --H, --OR or --CF₂ CF₂ Z; X is --Cl or --Br; and M is Na, Li, K orNR'₄.
 2. A process according to claim 1 wherein the temperature is fromabout 0° C. to about 50° C.
 3. A process for preparing a dioxolane ofthe formula ##STR31## wherein R'_(f) is --H, --C(O)Y' or Q';Y' is --OCH₂CH₂ X where X is --Cl or --Br; Q' is ##STR32## Z is --F, --N₃, --OC₆ H₅,--SR' or --OC₆ F₅ ; and R' is an alkyl group of 1 to 4 carbon atoms;comprising contacting at a temperature of from about -20° C. to about80° C. (a) 2-chloro- or 2-bromoethylformate or (b)bis(2-chloroethyl)oxalate or bis(2-bromoethyl)oxalate with a compound ofthe formula MCF₂ CF₂ Z in a suitable solvent; wherein M is Na, Li, K orNR'₄.
 4. A process according to claim 3 wherein the pressure is fromabout 10 kPa to about 6900 kPa and the temperature is from about 0° C.to about 50° C.
 5. A process for preparing a dioxolane of the formula##STR33## wherein: R_(F) is a perfluorinated alkyl group having 1 to 14carbon atoms and terminally substituted with --F, --Cl, --OR, --OC₆ F₅,--SR', --SO₂ R', --SO₂ F, --N, --CN or --C(O)OR', or said perfluorinatedalkyl group also containing ether oxygen;R' is an alkyl group of 1 to 4carbon atoms; R is an alkyl group of 1 to 4 carbon atoms, --CH₂ CF₃ or--C₆ H₅ ;comprising contacting at a temperature of from about -20° C. toabout 80° C. an ester of the formula R_(F) CO₂ R' with a compound of theformula MY' in a suitable solvent; wherein Y' is --OCH₂ CH₂ X, X is --Clor --Br; and M is Na, Li, K or NR'₄.